Binford's contribution to archaeology was as much on the theoretical as on the practical side. He advocated the concept of processualism, which argued that no site could be truly understood without an understanding of how it had been created, the corollary being that any excavation or archaeological investigation should begin with a theory against which the evidence could be tested. His 1962 article, "Archaeology as Anthropology" (American Antiquity, 28: 217-225) effectively began a new movement in archaeology, beginning from the "Old Copper Problem". In the process of analysing the use and exchange of copper artefacts in North America, he developed a theory about the development of cultures which was as much anthropology as archaeology. Binford's arch-adversary was François Bordes, with whom he argued over the value of Mousterian sites.